Such technique has been proposed, for instance, in Patent Document 1. An oil pressure controller disclosed in this Patent Document 1 has a pre-charge pressure control unit that after temporarily rapidly increasing a hydraulic fluid pressure, rapidly decreases the hydraulic fluid pressure then produces a shelf pressure for pre-charge and a capacity adjustment pressure control unit that gradually increases the hydraulic fluid pressure from a decreased point of a pre-charge pressure and produces a capacity adjustment pressure of a frictional engagement element, when inputting a range signal upon change of the range from the neutral range (N-range) to the drive range (D-range or R-range).
By rapidly decreasing the hydraulic fluid pressure after temporarily rapidly increasing the hydraulic fluid pressure upon the change of the range from the neutral range to the drive range by the pre-charge pressure control unit, preparation for an engagement of the frictional engagement element is promptly made, and after that, by so-called gentle pressure increase that gradually increases the hydraulic fluid pressure by the capacity adjustment pressure control unit, a shock when the frictional engagement element is completely engaged is reduced, thereby achieving both of completion of selection in a short time and reduction of the shock.
In a case of the technique disclosed in Patent Document 1, however, each of the shelf pressure and the capacity adjustment pressure upon the selection is uniquely set irrespective of brake-operating/nonoperating state. Although a degree of the shock transmitted to a vehicle is different between the brake-operating state and the brake-nonoperating state, this point is not taken into consideration at all. For this reason, there is still room for improvement in the achievement of both of the completion of selection in a short time and the reduction of the shock.
Further, from a different viewpoint, in the case of the technique disclosed in Patent Document 1, it can be estimated that each of the shelf pressure and the capacity adjustment pressure upon the selection is set to a compromise and intermediate hydraulic pressure with consideration given to both of the reduction of the selection shock and the vehicle startability, irrespective of the brake-operating/nonoperating state and driver's intention.
For this reason, under circumstances where the driver desires the vehicle startability, although sensitivity of the driver to the selection shock becomes lower, since each of the shelf pressure and the capacity adjustment pressure is set to a hydraulic pressure with consideration given to the selection shock, it takes a time to engage the frictional engagement element, then this causes deterioration of the vehicle startability. On the other hand, under circumstances where sensitivity to the vehicle startability is low, since each of the shelf pressure and the capacity adjustment pressure is set to a hydraulic pressure with consideration given to the vehicle startability, the shock occurs upon engagement of the frictional engagement element, then this gives an odd or awkward feeling to the driver, which is undesirable.